From: Gabe Black <gblack@eecs.umich.edu>
Date: Wed, 2 Jun 2010 17:58:08 +0000 (-0500)
Subject: ARM: Implement the clz instruction.
X-Git-Tag: stable_2012_02_02~1242
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=2c94bf7f30d3e9febe30485cf7182b650f48f4d5;p=gem5.git

ARM: Implement the clz instruction.
---

diff --git a/src/arch/arm/isa/insts/misc.isa b/src/arch/arm/isa/insts/misc.isa
index 09d27360e..c673372bb 100644
--- a/src/arch/arm/isa/insts/misc.isa
+++ b/src/arch/arm/isa/insts/misc.isa
@@ -174,6 +174,16 @@ let {{
     decoder_output += RevOpConstructor.subst(rbitIop)
     exec_output += PredOpExecute.subst(rbitIop)
 
+    clzCode = '''
+        Dest = (Op1 == 0) ? 32 : (31 - findMsbSet(Op1));
+    '''
+    clzIop = InstObjParams("clz", "ClzInst", "RevOp",
+                           { "code": clzCode,
+                             "predicate_test": predicateTest }, [])
+    header_output += RevOpDeclare.subst(clzIop)
+    decoder_output += RevOpConstructor.subst(clzIop)
+    exec_output += PredOpExecute.subst(clzIop)
+
     ssatCode = '''
         int32_t operand = shift_rm_imm(Op1, shiftAmt, shiftType, 0);
         int32_t res;